Combitec: SRAM 500

The SRAM 500 was available in two models, one which supplied 512K of
SRAM and other supplied 1MB of SRAM. The SRAM could be used as an
ordinary RAM expansion, or using the supplied software it could be used
as a reset-proof RAM disk. The SRAM-500 also had a hard disk controller
which is the same one as used in the Combitec HD20/HD40.